Tunnel segment and method of making same



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| FINE. ET'AL TUNNEL SEGMENT AND METHOD OF MAKING SAME Original FiledJuly 5l, 1940 16 Sheets-Sheet l0l MoJ@ Mw Jan. 9, 1945. FINE ET AL2,366,961

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l TUNNEL SEGMENT AND METHOD OF MAKING SAME y Original Filred July 31,1940 16 Sheets-Sheet l5 Jan. 9, 1945.

L. FINE ET AL TUNNEL SEGMENT AND METHOD OF MAKING SAME originali FiledJuly 51, 1940 16 Sheets-Sheet 16 Lewis Harle @M y? ying hasjhad to be.placed between the rings) to Patented Jan. 9, 1945V TUNNEL S LewisFine,V Bethlehem,

EGMENT AND Mn'rnn or MAKING SAME t and Harley B. Kelchner, 'i

L ower Saucon Township, Pa., assignors to Bethlehem Steel Company, acorporation of Pennsylvania original application July 31,194 v ded andthis application July 25,

348,610. Divi 1941, Serial No. 404,010

17 Claims.

V'l'.his invention relates to thev method and apparatus `formanufacturing tunnel lining segments of structural steel and is moreparticularly adapted to the mannerof assembling and holding the parts ofwhich the tunnel segments areiormed to facilitate welding of the sameto. gether to produce a single unit, and is a division oibur copendingapplication, Serial No. 348,610,

' tiled July 31,1940, now Patent No. 2,324,919.

Our invention'is especially adapted for use in. making tapered tunnellining segments of struczturalV steel shapes having; side and f end edgeflanges which will have true contact engaging surfaces when the segmentsand tunnel lining rings are secured together, but it is also adapted forUmakingftunnel segments having parallel side anges equally as Well. f

' At the present time'the usual practice in producing cast taperedsegments for constructing curves in tunnels, which is the kind mostcommonly used heretofore, is to have the segments' assembled in a ringon ya tapered base ring and horizontally machined on the side flanges ofthe ring by circular planing or milling. The general practice is toprovide the taper on one face only. If it is essential that both facesbe tafpered, or one half of the taper on each face, the

machiningjroperation is performed on both faces with two tapered baserings.

Tapered casi', segments have also been l produced by planing or millingthe side flanged `faces of individual segments mounted on correctlycalculated base plates all of which requires special castings andmachining. f

f In forming tapered tunnel segments of struc- Northampton County,

0, Serial No.

make the joints radiate properly from the center point of the curve. Inother cases special castings have had to be used, and soft Vwood packingor theflike has also been used to some extent. l One of the objects ofour invention relates to producing a tunnel. segment formed ofstructural material provided 'with side and end flanges which-havetrue-contact engaging si'de surfaces.

tural steel shapesl or in one piece of plate metal in a press .by meansof bending dies, the outer side.- faces of the side flanges of the ringswill I be. 90 to the outer'surface ofthe tunnel lining.

.This does not give true contact engaging surfaces when the rings aresecured together, as the 'side anges will engage or heel at theVoutsidexorinside' diameter ofthe ringsv and have a gap at thev adjacentsurface. 'if ythis gap is not too great it can'be closed by meansofrdraw l ing up on the bolts which connect the side flangestogether.1f, however, the gap exceedsthe ltol-v erances allowed it wouldhave to be closed by means of a seal weld, which might be a source.

of trouble, for the contractor.

Theimportance of this-problem has beencon- -sidered andlprovided,L forin various waysin some of the important. tunnels built and in some casesin constructing tunnels around curvesl iron packl through the holdingjig Another object of our invention relates to the method -of formingtunnel lining segments. having side andend flanges having true contacten gaging side surfaces.

Another object of our invention relates to the method of.iormingatapered tunnel liningsegment having a skin plate with parallelside edges. Another object of our invention relates tothe method offorming a tunnel lining segment havextending parallel to eachy ing vtheside flanges other with a skin plate of varying width.

VAnother object of our invention relates to the manner of assembling andclamping the parts of which the segment is formed in a jig having cheekplates with inclined faces adapted to produce the desired inclination ofthe side flanges of the segment.y

Another object ofV our invention relates to the construction of the jigwhereby the cradle with the structural parts of the segment mountedthereon lmay be rotated'at different angles to facilitate the weldingoperation.v

A further object of our invention relates to Y the manner of assemblingand removing the segment from the jig.

With'the foregoing and other objects/in view, the invention 'will bemore fully described hereinafter, rand will be more particularlypointedout in the appended claims.

Referring. now to the accompanying sixteen sheets of drawings which forma part of this specification.and on which like.' characters of`reference indicate like parts.

' "Figure l is a perspective view of theholding Figure 2 is a vVerticallongitudinal section taken on kthe line 2-2 ,of Figure 3 with theoutsideframe in section to showr more clearly the trunnion lbearings for thesame;

Figure 3 isa transverse section through the holding jig taken on theline 3-3 of Figure 2;

Figurea is a transverse section throughone of the clamping jacks takenon the 'line 4 4 of 55 Figure 5 is a' Figure 5;

longitudinall section through one of the clamping jacks taken on theline 5-5 of Figure 4;

Figure 6 is a transverse section through the cradle taken on the line3--3 of Figure 2, but drawn on an enlarged scale to show theconstruction more clearly;

Figure 7 is a top plan view of the cradle;

Figure 8 is a detail section view of the outside frame turningmechanism-taken on the line 8-8 of Figure 9;

Figure 9 is a top plan view of the outside frame turning mechanism;

Figure 10 is a front elevation of the cradle turning mechanism;

Figure 11 is a horizontal section through the cradle turning mechanismtaken on the line II-II of Figure 10; i

Figure 12 is a side elevation of a portion of the cradle showing themovable side for the same drawn on an enlarged scale;

Figure 13vis a side elevation oi a portion of the stationary side of,the cradle;

Figure 14 is a'front elevation ofthe movable end of the cradle;

Figure 15 is an end elevation of the movable end of the cradle;

Figure 16 is an end elevation of the xed end of the cradle;

Figure 17 is a side elevation of one of the holding clamps; Y

Figure 18 is an end elevation of the said clamp;

Figure 19 is a, detail showing the false key segment and the manner ofholding the same in the cradle;

Figure 2O is a top plan view of one of the hold down beams;

Figure 21 is a side elevation of the hold down beam shown in FigureFigure 22 is a side elevation. of one of the hold down pins;

Figure 23 is a side elevation of the outer side of the fixed side cheekplate;

Figure 24 is a transverse section of the same taken on the line 24-24 ofFigure 23 showing a, ribbed section;

Figure 25 is a section taken on the same line as Figure 24, but showinga solid section;

Figures .26, 27, 28 and 29 illustrate sections taken on the line 29-29of Figure 23 showing the different angles of the sides of false cheekplates we may use;

Figure 30 is a side elevation of the inner side of the movable sidefalse cheek plate;

Figure 31 is a transverse section of the same taken on the line 3I3I ofFigure 30 showing a ribbed section;

Figure 32 is a section takencn the same line as Figure 31, but showing asolid section;

Figures 33, 34, 35 and 36 illustrate sections taken on the line 36-36 ofFigure 30 showing the different angles of the sides of false cheekplates we may use;

Figure 37 is a side elevation of a tunnel lining; t

Figure 38 is a, diagrammatic end elevation of one of the tunnel rings;

Figure 39 is a partial transverse sectional view of the tunnel liningtaken on the line 39-39 of Figure 40;

Figure 40 is a longitudinal section View taken on the line lll-40 ofFigure 39;

Figures 41, 42, 43 and 44 are detail sections drawn on a larger scaletaken on the lines 4 I-4I, 42-42, 43--43, and i4-44,4 respectvely,y OfFgportion oi a,

ure 40;

Figure 45 is a side elevation showin-g a ring for a tunnel lining havinga 32-10" diameter with a 41/2" taper;

Figure 46 illustrates the inclination of the sides of the tunnelsegments at the meeting ends of each of the segments of the ring shownin Figure 45;

Figure 47 isa detail section through the high side on the horizontalaxis of the meeting ends oi the. flanges of two taper rings madeaccording to our invention having a true fit;

Figure 48 is a detail section through the low side on the horizontalaxis of the meeting ends of the anges of two taper rings made accordingto our invention having a true iit;

Figures 49 and 5l) are detail sections through the high and low sides onthe horizontal axis illustrating the condition which occurs when themeeting ends oi two rings have their flanges disposed at 96 to theoutside of the tunnel lining;

Figurel is a detail section through the meeting ends of two tunnellining rings having par,- allel side flanges;

Figure 52 illustrates the manner of forming a taper segment by incliningthe side bulb angles and using a skin plate of uniform width; and

Figure 53 shows a tunnel segment having parallel side flanges andprovided with a skin plate formed in a continuous rolling mill withoutbeing trimmed; in this manner the plate varies somewhat in width. Y

Referring now to the various characters of reference on the drawings:

The numerals I and 2 indicate the trunnion pedestals for supportingv thejig which are formed of metal plates cut into the desired shape andwelded together. These trunnion pedestals are each mounted on and weldedto base members 3 formed of I-beams.

A bearing block 4 is welded to the upper end of each trunnion pedestal Iand 2 which are provided With roller bearings 5 held in position bymeans of' a cap washer 5. Tiunnions 'i and 8 are journaled in rollerbearings 5 each having an inwardly extending en@L portion inserted in ahole in the trunnion bearing blocks 9 of the outside frame I3 and weldedthereto as at li. The trunnion 8 extends outwardly from the bearingblock 4 and has a worm wheel I2 keyed thereto meshing with a worm I3which has its shaft I4 journaled in. bearings I5 mountedron a bracketVI6 secured to the upper portion of the trunnion pedestal 2. A beveledpinion I 'l is mounted on one end of the shaft I4 of the worm I3 adaptedto `mesh with a Ibeveled pinion i3 keyed to a shaft I 9 journaled inbearings 29 which is mount ed on a bracket 2l secured to the upperportion of the trunnion pedestal 2 adjacent to the bracket I6. The outerend oi shaft i9 is provided with a crank arm 22 havingr a handle 23 bymeans of which the outside frame I9 may be rotated vertically.

This outside frame It comprises a rectangular frame formed of spacedchannel shaped side and end members 24 and 25, respectively, disposedwith their fianges extending inwardly toward each other and connectedtogether at their ends by means of gusset plates 26 and at intermediatepoints by means of plates 21 and ribs 28.

As indicated more clearly in Figures 3 and ll va journal bearing 29is'secured centrally to each Aof the inner channel shaped members of theend l frame members 25 of the outside frame i9.

meedoet.

a lworin wheel 31 "keyed: thereto `meshing 'with "a WormV 38" which hasits shaft 3l)y `journaled in bearings 4llmountedon a bracket El; securedto-fone of the outer channel shaped end members '2 of' the outside'frame Nl; The outer end. off' the sha-ft 39 is provided with a erankvarm 4-2 having a handle 43 by means of which the cradle 35 can berotated at right'an-gles to the rotation of the outside frame 'I 0.

'The-cradle 352011 which the structural parts -of the tunnel segmentsyare assembled' and 'held' during the welding'operation isn preferably'builtup of a, plurality of vparts Welded' together, and corr"prisesarc-shaped'I longitudinally extending spaced sills 4'4 connectedvtogether at their ends by' means ofijat plates-fand 4S.. Theselongitudinal 'sills 414 are. vconnected ,togetherat spaced interval'shymeans of transverse. :sills 41",. each havingupwardly extendingV endportions which are con"r nested together'atzone side. of' the cradlebyvmeans oflhorizontally disposed plates *'48 Vto which :the movableside ofVA the cradle'is attached, While the opposite. ends :of.theftransverse sills. 41 Aare conf nectedtogetherhy means of'.avertically extendYving; side plate 49Tformingthe'stationary side wal-l'havingfhorizontally extending reinforcing flanges welded, thereto asat'.The longitudinally .and transversely extending sills 44 and 41 arelfurther reinforced and connectedat their centralfk and intermediateportions hy means of rectan-r gular and gusset Vplates 5| and i2',reslnectivelyik Thesegment is assembled? withthe outer portion or skinplate l32.resting on the cradle and the flanges '|36 andend plates MJ)vextending feut-l Wardly therefrom. This outer portion. is of greaterdimension than; the outwardly .extending ends ofthe flanges L36... sothat .td allow the -parts ot they segment .to'be assembled and. thefinished segment to be removed therefrom. one. side .and endoi the.cradle has, to hemovahle, and for .this purpose. the end plate 45iis-.provided with holes 53101' receiving holtsfdand taperedperiorations .5,5 for receiving tapered pinsi56. The mevahle ,end of thecradle lv is. reinforced by vmeans'of anges 58. Welded theretoand to abaseplate which is, seated on. theend plate and has 'a notchat its innerend as .at tfor receivingy the lower edge of :theend plate L40 of the.tun-nel segment fandsaid base plate `is further provided with slotstland tapered perforations .which register Withthe holes 153. andthetapered pertorations 55. inthe .end platet5.v adapteditoreceive thebolts- 54 .a.nd theftaperedpins-SQ. .These'holts 54. and tapered pins 5dare slotted as at 53 to're seine; keys .64 fiorjcla-mping the-movableand of the icrad-le 'to the; end zplatew. Thestationary Yendfwall |54attire/opposite enda'of vthe vv :radle is providedWitl'rrei-nforeing'ilangesGhandi has its lower end' welded tothe endplate yAtwwhich is provided with a vnoten 61; at its'innerend'. for

receiving the.- lovzer edgeof .the other end .plate t4-0 the-oppositeendzof thesegment.

moi-.der 'vrijheid meenapirates` ofvtnezfsegment securely in position incontact With the end walls @of the cradle. during the (weldingeperation,

clamps 6E. areeplacedrorerzthe. onteredgesfofmthe same'andheld .positionlay-means of BQ..

'The membresa@ or .the cradle n remaches,

to! the.1lmrizentally disposed; side plates 481 in a. similarlmanner tothat-'ofthe'.movable end of thecradle The said :sideplates 4'8: havefthe holesllll `and :taperedperforations 'l2 for receiping vbol-ts'lsfand'tapered pins i4. .This movable. side "l0-ofthe cradleisi-reinforced by means of flanges l1 5, .Welded thereto, yand hasl ahorizontal-ly extending .plate 1,8 .which isy sea ed on the base platen,having slots fH and tapered perfora-v trons'rs therein which registerwith me. holes.

'Hf and taperedipert'orations [2 in thefbase plates 4d for receiving thebolts' T3 and taperedlpins-"EIL` These bolts 13 and tapered pins y14 arealso slotted at 19 for Vreceiving'keys 8U; forclampingthe movable'sideF0 lofthe oradleto the side plate 4-, in Iordente further reinforceandhold `the s movablevside 'w of the cradle position it is. providedwith brackets *8| which` vextend into notches @2in-the side plate @8.

rThe Asta,1ieria.1-'y'and 'movable side Walls 49 andi 'l0 of the cradleare perforated to receive bolts 83"-forattachingj the cheek plates` 8f4and 85" thereto. These cheek plates which are/'more clearly illustratedin `FiguresfZS to 36, inclusive, are each preferablyformed of a`plate-'havingI one plain side surface 86e fory engaging thevsi'deflanges |136 ofthe. vassembled' segment While the other side isformed-With ribs 8T and pads 88 havingthreaded holes "formed'thereinasat89'1orx receivingwthe threaded ends Aofthe-bolts $3. As "these cheekplates "look similar the. two centrally disposed pads '881 on the'stationary' cheek plate 841 are placed' in a ydiffer-'ent,positiontha'nthoseon-the movable cheekfplate' 85 in orderf'to more quickly designatethe ycheek plates in assembling'. vThe cheek-plates areffurther providedwith. lifting lugs 9U to 'facilitate movement of thesame. As statedabove one side 4of each cheekr plate isI plain as at 86 with'a-n ang-1esubstantiallyr 90 to the `edges and is adapted to engage-the sideflanges |36 of theftunnel segment WhiI-efthe other'side ofgthe cheek'lplates will have an inclination corresponding'to the outer i'aee of theside anges of the segment which may be-QO ofthe' angles indicatedinl-full linesi'n Figures 24', 25, 27, 28, 29, 31, '32', 34, 35 and 36to` the angle indica-ted in dotted lines in these figures. The cheekplates may also be made of sol-id` Vhars as shown in the sectionsinFigures 25y to 27 and 32 to 34, inclusive. Y

Threaded `nuts V9 Fare welded to thev central and end portions'of' thestationary and movable sides of thecradle onthe-'center sides of theIsameat theirupper edges. Each of these nuts 91 hasl a hold down `post 92with its lower end threaded thereinwhieh is further secured thereto bymeans of va pin 93. The nuts 9| attached to onesid-e wall 4119 at onevside' of the cradle are disposed in parallel ralignment with the nutson the lopposite sidewall;llll and are connected together by hold downposts which are: sletted asfat 9-9"for receiving .keysA adapted to clamptheI hold downY beams 9i-in .posi-tion. The holes 91 each have a holddown fpm `|1|l I mounted therein the 'lower 'jend `ofwhicli 'engages'the side ange |136 of the segment. These hold' down-.pinsare eachadi'ustablyheld' in position by means; of keys |02 ,wizelrextendfthrough slots i3-"and |104l in 'the channels 95 and the hold down pins,respectively. In order to facilitate the manipulation of the hold down.beams 94 the hold down pins |0| areF jacent side the flanges areconnected togetherr by means of a clamping block |08 which extendstherefrom and has a recess |09 formed therein for engaging the flangesof the central T-shaped reinforcing chord member |33 of the tunnelsegment.

The longitudinally extending sills 44 at their upper edges have threadednuts welded thereto at spaced intervals, in each of which is threaded anadjustable set bolt adapted to engage the outer face of the skin plate|32 of the segment and support the same in the cradle. These set boltsare adjusted in the desired position by means of a template or the like(not shown) and then preferably weldedpermanently in the adjustedposition.

The T-shaped lchord member |33 is held centrally and the webs |38 of thespecial bulb angles forming the side flanges |36 of the segment areclamped securely against the inner plain surface 86 `of the cheek plates84 and 85 by means of a plurality of pairs of jacks ||2, each comprisinga plunger ||3 for engaging the stem |34 of the T-shaped central chordmember |33 and a sleeve ||4 engaging the web 38 of the special shaped pbulb angle. The sleeve |4 is keyed to the plunger ||3 by means of a bolt||5 which is threaded as at -||6 in a hole in the sleeve and has areduced plain end ||1 extending into a keyway ||8 in the plunger. Saidplunger and sleeve are slotted as at I9 and |20, respectively, forreceiving adjustable wedges |2| for holding the jackl ||2 in the clampedposition. The sleevekis further provided with reinforcing pads |22welded theretofor backing up the slots and a U-shaped handle or liftinglug |23 and feet |24 adapted to rest on the inner surface of the skinplate |32 of the segment. We may also in some cases use clamping postsin addition to the jacks as indicated at |25 in Figure 1.

The segments are assembled from the inside in forming the tunnel liningrings, and as the outside of the tunnel is of greater diameter than theinside it is necessary to have a key segment which is placed in positionafter the other segments in the ring have been assembled. This requiresthat one of the segments engaging the key be made shorter than the othersegments with one end plate |40 inclined at a greater angle than theother. As the-cradle is adapted to hold assembled parts for segments oflonger-length it is sometimes necessary to illl in this space in thecradle by means` of a false key member |26 Vas indicated in Figure 19.In this Figure 19 the inner length, |29 a'slightly shorter segmentdisposed adjacent to the key segment |30, in the tunnel lining rings|3|. As indicated in the drawings, each segment comprises an outer skinplate |32, a centrally disposed T-shaped reinforcing chord member |33having the end of its stem |34 connected by means of intermittentwelds|35 and side flanges |36 extending inwardly from the side edges of theskin plate |32, each formed of a bulb angle of special rolled shapehaving a bulb |31, web |38 and flange |39. The skin plate |32, T-shapedreinforcing chord member |33 and the bulb angles are each cambered toconform to the cylindrical contour of the tunnel lining and have theirends connected together by means of end plates |40, which are ofslightly greater height than the depth of the segment. These end plates|40 are secured to the skin plate at the outside and inside of said skinplate |32 by means of con.. tinuous welds |4| and |42, respectively,while the ends of the webs |38 and flanges |39 are chamfered as at |43to receive welding material |44 as indicated in Figures 4l, 42 and 44.As shown in Figure 43 the end edges of the flanges of the T-shapedreinforcing chord member are also chamfered at |45 to receive weldingmaterial |46, while the end of 'the stem |34 adjacent to the skin plateis coped to allow the weld |42 to extend continuously therethrough asindicated at |41 in Figure 39. The side flanges |36 and end plates |40have bolt holes |48 formed therein for receiving bolts |49, eachprovided with a nut threadedvjthereon by means cf which the segments areconnected together. yTo prevent leakage around these bolts |49, theouteredges of the bolt holes |48 are chamfered as at |5| to receive packingor calking material |52 such as lead or the like, which is held inposition by means of Washers |53. After each ring of the tunnel lininghas been assembled and placed in position the inner edges of the endplates of the segments are Welded as at |54, the said edges havinggrooves |55 formed therein for this purpose as. indicated in Figures 39and 41 to 43, inclusive. The inner edges of the side flanges |36 arealso seal welded as at It` in the manner shown in Figure 40. Thesegments are further provided with threaded holes in the skin plates |32to permit grout to be forced through the lining to ll any space aroundthe same after the lining is in place, each of these holes subsequentlyybeing closed by a plug |51.

vIf the tunnel lining is straight as illustrated in the left hand sideof FigureI 37, the side flanges |36 of the segment will be parallel toeach other and disposed atan angle of to outer surface .of the skinplate |32 and have a true llt as indicated in Figure 5l. When the tunnellining extends around curves or is inclined at an angle to the straightportion of the tunnel lining the segments and rings have to betapered asindicated in Figure 45 and the right hand side of Figure 37.

If thetunnel segments and rings are tapered and the engaging surfacesofthe side flanges are disposed at -an angle' of 90 which is the usualpractice in forming tapered segments for tunnel lining rings, the sideflanges at the high and low pointsof the ring will heel as at |58 at theinner or outside surface of the ring and have a gap |59 at the -adjacentsurface of the ringin the manner illustrated in Figures 49 and 50.

With our invention we are able to produce tapered segments for a tunnellining in which the ergaging surfaces of theside flanges have a true InFigures 38 and 455 to 48, inclusive, we have

